Patent GB-190111368-A (GB)
Title: Improvements connected with Filters and in Apparatus for Automatically Alternating the Delivery of Liquid or Sewage thereto more particularly applicable to Bacteriological Filters
Inventor: HALLER JAMES CRACROFT
Filed: 1901-06-04
Granted: 1902-04-24
Abstract: 11,368. Haller, J. C., and Machell, R. H. June 4. Sewage and foul waters, treating bacteriological processes; precipitating; filtering.-Relates to the automatic delivery of sewage or other liquids and their discharge from three settling-tanks or filters, in repeated cycles, the liquid being allowed to rest for a given period in each tank and being drawn off slowly, a sufficient interval being also allowed for aeration of the filtering-materials after each discharge. The sewage from the main sewer a passes through one or both of the detritus tanks b, c, where floating matter and sediment are collected. Thence the sewage passes to a tank d, from which it is distributed to tanks for treatment by anaerobic micro - organisms. The sludge from these tanks is forced through conduits f to pits g where it solidifies. The effluent from the tanks is distributed by a conduit to aerobic filter beds A, B, C, D, of which one is always held in reserve. The floors of these filters are drained by agricultural drain tiles, and above these are layers of limestone and coke, breeze, or other hard materials, intermixed with sufficient limestone to take up the carbonic acid from the liquid. The liquid is distributed evenly and slowly over these filters by means of horizontal channels, shown in Fig. 1, which are supported at the surface of the bed by short vertical pipes resting on a solid foundation in order to render the channels independent of the bed and thereby to insure an equal distribution of the liquid. The pipes supporting the bed are filled with the filtering-media. The slow filling and discharging of the filter beds is automatically effected by the overflow from the bed last filled. Thus, when A is full, the liquid overflows by a pipe o into the compartment p of its own closing chamber P (shown separately in Fig. 4), and raises the floating arm r, through which the liquid flows to a chamber s, and there it raises the floating cylinder t and thereby actuates a lever u which slides a valve v over the inlet pipe o of the bed A and cuts off the supply. From the chamber s, the liquid passes on by a pipe not shown to the opening chamber of the bed B, which is exactly similar to that of A shown at x, Fig. 4. Here it raises the floating cylinder y and thereby operates the lever z which moves the slide valve v so as to open the inlet to the bed B. Also, when the liquid has reached a certain height in A it flows by a pipe not shown to the outlet chamber 6 (shown separately in Fig. 6) of the bed C and raises the balance float 6 so as to depress outlet pipe 8. The liquid in the bed C is thus discharged through its outlet chamber and the pipe 8 to a conduit 11 whence it is distributed over earth filter beds 12 for final filtration. In a similar manner, when the bed B fills, it automatically closes its own inlet valve, opens the inlet valve of the bed C, and opens the outlet valve of the bed A which has been resting, and the cycle is repeated as long as the liquid flows into the beds A, B, C. The bed D replaces one of the beds A, B, C from time to time, as required.